Brake



K. E. LYMAN 1,749,188

BRAKE Filed Ju1 y 16, 19 7 KE JETH E.LYMAN ATTORNEY Patented Mar. 4, 1930 UNITED STATES PATENT OFFICE KENNETH E. LYMAN, OF CHICAGO, IIIZIII'JIIEI'OIS, ASSIGNOR TO IBENDIX OF CHICAGO, ILLINOIS, A CORPORATION OI ILLINOIS BRAKA Application filed July 16,

This invention relates to brakes and is illustrated as embodied in an internal expanding brake for an automobile.v An object of the invention is to provide simple means for I! adjusting the brake, preferably automatie cally.

In one desirable arrangement the brake includes a pair ofshoes arranged end toend, and one of which is preferably anchored, and which are connected by a novel joint' which can be adjusted to separate the shoes to compensate for wear.

In the illustrated embodiment the joint between the shoes includes a cam which is adjusted angularly to provide the adjustment and which I prefer to arrange for movement-about a radial axis extending between the ends of the shoes.

I also prefer to provide at the above-described joint a stop for determining the idle positions of the shoes and which is preferably arranged to prevent lateral movement of the shoes.

' 3-3 of Figure 1, showing the arrangement of the cam; and

Figure 4 is a perspective view of one end of one of the brake shoes showing its formation for en agement with the cam.

c In t e arrangement illustrated, the brake includes a rotatable drum 10 at the open side] of which is a backing plate 12 and withm which are arranged three brake shoes 14, 16,

and 18. The shoes are applied by a device such as a double cam 20 against the resistance of a main return spring 22 which urges the shoes 14 and 18 away from .t e drum, and

I927. Serial No. 206,152.

the shoe 16 away from the drum. The shoe BRAKE comm,

l4.is anchored at its lower end on a fixed pivot 26 while the shoe 16 is forked at its end to straddle the, end of the shoe 14 and is anchored on a fixed pivot 28.

The present invention has to do with adjusting the brake by separating more or less the shoes 16 and 18 or their equivalents, by a novel floating joint between the shoes and through which the shoe 18 acts to force the shoe 16 against the drum to apply the brake.

In the particular embodiment illustrated,

each of theshoes 16 and 18 is formed at its end with a groove 30 for a cam 32 rotatably mounted in a carrier 34 between the ends of the shoes and moving with the shoes when the brake is applied and released. The carrier 34 is provided with a device such as a finger 36 enga ing a groove 38 is an eccentric 40 adjustafioly clamped by a nut 42 to the backing plate 12. The finger 36 is urged toward the bottom of the groove 38 by spring 24 so that the eccentric 40 serves as a stop adjustably positioning the shoe when the brake is released. The finger 36 also interlocks with the walls of the groove38 to prevent lateral movement of the adjacent ends of the shoes 16 and 18.

which is engaged on the application of the brake after excessive wear by a stationary spring pawl 48 secured to the backing plate 12.- If there has been excessive wear in the brake the pawl 48 causes the rack 44 to shift one tooth when the brake is applied, thus turning the cam 32 to separate the shoes 16 and 18 to compensate for the wear.

While one illustrative embodiment has been described in detail, it is not my intention to limit the scope of the invention to that particular embodiment or otherwise than by the terms of the appended claims.

I claim: p v

1. A brake comprising, in combination, an anchored shoe and an unanchored shoe shoes, and means for automatically adjusting said joint to separate the shoes to compensate for wear. v 2. A brake comprising, in combination, an anchored shoe and an unanchored shoe arranged end to end, a joint connecting said shoes and, including a floating cam between the shoes, and means for turning said cam to separate the shoes to compensate for wear.

3. A brake comprising, in combination, an anchoretLshoe and an unanchored shoe arranged end to end, a joint connecting said shoes, and means for automatically adjusting said joint to separate the shoes to compensate for Wear, said means including a ratchet moving with the joint and a statlonary pawl operatlvely engageable with the ratchet and shifting the ratchet in case of excessive wear ofthe shoes.

4. A'brake comprising, in combination, a a pair of shoes arranged end to end, and a floating joint between the shoes including a cam engaging the adjacent ends of the shoes and arranged with its axis extending radially between said ends.

5. A brake comprising, in combination, a pair of shoes arranged end to end, and a floating joint between the shoes including a cam engaging the adjacent ends of the shoes and arranged with its axis extending radially between said ends, and said ends being grooved to embrace the cam.

6. A brake comprising, in combination, a drum, an anchored and an unanchored shoe arranged end to end within the drum and connected at their adjacent ends bya floating joint, means engaging the unanchored shoe at its free end to apply said shoes to the drum, and means engaging the floating joint be tween said shoes to automatically take up for wear of the shoes.

7. A brake comprising, in combination, a drum, an anchored shoe and an unanchored shoe arranged within said drum and connected end to end by a floating joint, means engaging the unanchored shoe at its free end to apply said shoes to the drum, a backing plate, and means extending through the backing plate and coupled with the floating joint to adjustably position the shoes. 4

8. A brake comprising, in combination, a

. drum, an anchored shoe and an unanchored shoe arranged within the drum and connected end to end by a floating oint, means engaging the free end of the unanchored shoe to apply said shoes to the drum, and means including arotatable cam positioned between the ends ofsaid shoes and operable to adjustably-position the shoes.

9. A brake comprising, in combination, a drum, a backing plate, a pair of brake shoes arranged end to end within the drum and connected by a floating joint, means operatively engaging one end of one of the shoes to apply both shoes to the drum, and means carried by the backing plate operatively engaging the floating joint between the shoes to adjustably position the shoes.

10. A brake comprising, in combination, a drum, a backing plate, a pair of brake shoes arranged end to end within the drum and connected by a floating joint, means opera- -tiv-ely engaging one end of one shoe to apply said shoe to the drum and through said floating oint to apply the other shoe to the drum, and means operatively engaging said floating joint to adj ustably position the shoes.

11. A brake comprising, in combination, a

drum, a backing plate, a pair of brake shoes arranged end to end within the drum and connected by a floating joint, means operatively engaging one end of one shoe to apply said shoe to the drum and through said floating joint to apply the other shoe to the drum, and means operatively engaging said floating joint to automatically actuate the same to take up for wear of the shoes.

12. A brake comprising, in combination, a drum, a pair of brake friction members arranged end to end therein, and a part positioned between the adjacent ends of said friction members and rotatable about an axis extending radially of the drum to adjustably position said members, said. part being held by said.sh0es against displacement radially thereof.

13, A brake comprising, in combination, a drum, a pair of brake friction members arranged end to end therein, and a part positioned between vthe adjacent ends of said friction members and rotatable about an axis extending radially of the drum to adjustably position said members, said part being held by said shoes against displacement radially thereof, and means engaging said part and automatically operable to rotate the part to take up for wear of the friction members.

14:. A brakecomprising, in combination, a drum, a backing plate, apair of brake friction members arranged endto'end within the drum, means positioned between the ends of said friction members and having a part rotatable about an axis extending radially of the drum to adj ustably position said members, automatically operable mechanism coupled with said part'to rotate the part to take up for wear of the friction members and an eccentric rotatably supported upon the backing plate and coupled with said means and operable to adjustably position said members.

In testimony whereof, I have hereunto signed my name.

1 KENNETH E. LYMAN. 

